1. Field
This document relates to a touch sensor integrated type display device capable of recognizing a user's touch, and more particularly, to a touch sensor integrated type display device which is capable of increasing the sensitivity of a touch sensor by reducing the amount of change in electrostatic capacitance caused by a touch driving electrode.
2. Related Art
Various input devices, such as a keyboard, a mouse, a trackball, a joystick, a digitizer, and the like, are used to configure an interface between a user and home appliances or various information communication devices. However, the use of the above input devices requires the user to learn how to use them and involves inconvenience like the space occupied by them. Accordingly, there is a growing demand for input devices which are easy and simple to use and can reduce malfunctions. In response to this demand, a touch sensor was proposed to enable the user to directly touch the screen with their finger or a pen to input information.
The touch sensor is simple to use, has less malfunctions, and enables the user to input without using an additional input device. In addition, the touch sensor can be applied to various display devices because it enables the user to operate it quickly and easily through content displayed on the screen.
Touch sensors can be classified into add-on type and on-cell type. In the add-on type, a display device and a touch panel having a touch sensor are separately manufactured, and the touch panel is attached onto an upper substrate of the display device. In the on-cell type, a touch sensor is directly formed on the surface of an upper glass substrate of a display device.
However, the add-on type sensor has a structure in which the completed touch panel is mounted on the display device and has various problems, such as increased thickness or reduced visibility due to low brightness of the display device
In addition, the on-cell type touch sensor has a structure in which a touch panel is formed on the upper surface of the display device and can have a reduced thickness compared to the add-on type but still has the problem of the increase in entire thickness due to a driving electrode layer, a sensing electrode layer, and an insulation layer for insulating the driving electrode layer and the sensing electrode layer which constitute the touch sensor.
Accordingly, a touch sensor integrated type display device that enables a touch sensor' touch driving electrodes and touch sensing electrodes to also serve as common electrodes for the display device was devised in order to solve the prior art problems.
In the conventional touch sensor integrated type display device, various shapes of pixel electrodes are configured in a complex way within a touch unit pattern, which is created by dividing common electrodes to use them as touch driving electrodes and touch sensing electrodes. With this complex configuration, common electrodes and pixel electrodes used for a display driving operation and touch driving electrodes or touch sensing electrodes used for touch recognition are located adjacent, and become sensitive to static electricity coming from the outside.